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Homework Help: How to solve this definite integral

  1. Feb 9, 2010 #1
    1. The problem statement, all variables and given/known data

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    3. The attempt at a solution

    I have no idea how to start this integral. Can anybody give me a hint to start it off?
    Thank you.
     
  2. jcsd
  3. Feb 9, 2010 #2

    Dick

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    Sketch a graph. Anything strike you about the relation between the part of the graph for x<0 vs x>0?
     
  4. Feb 9, 2010 #3
    Well I noticed that x>0 is the reflection of x<0 except with negative values. Does this mean that the answer is 0? Also is it even possible to solve this integral?
     
  5. Feb 9, 2010 #4

    Dick

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    No, you aren't going to get far trying to find an indefinite integral. But the definite integral is zero. In general, if f(-x)=(-f(x)) then the integral over a symmetric interval around zero is zero. You can formally show this by splitting the integral into two parts and working out their relation by doing the substitution u=(-x).
     
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